Vehicle-brake.



l. E. MCCRACKEN.

VEHICLE BRAKE.

APPLICATION HLED June 2s. 1915.

l ,2 l 4,046 Patented Jan. 30, 1917.

2 SHEETS-SHEET l.

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I. E. MCCIIACKEN.

VEHICLE BRAKE.

APPLICATION FILED IuNE 28. I9I5.

2 SHEETS-SHEET 2- INVENTOR Patented J an. 30, 1917.

WITNESSES ISAAC E. MCGRACKEN, OF PITTSBURGH, PENNSYLVANIA.

VEHICLE-BRAKE.

maracas.

Specification of Letters Patent.

Application led June 28, 1915. Serial No. 36,805.

To aZZ whom t may concern:

Be it known that I, ISAAC E. MCCRAGKEN a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have l invented a new and useful Improvement in Vehicle-Brakes, of which the following is a specication.

This invention relates to vehicle brakes, and particularly to an emergency brake ario ranged to exert a frictional contact with the roadway and which can be utilized in case the ordinary brakes get out of order or refuse to work, and also to hold the vehicle stationary when facing up a grade.

The object of the invention is to provide a simple brake of this kind which can be readily applied to any vehicle, which can be manufactured at low cost, which is very eiiicient and can be easily manipulated, which serves to prevent skidding on a slippery pavementJ and which will also hold the vehicle stationary when facing up a grade so that the ordinary brakes can be slacked 0H to enable the engine to be started without allowing the vehicle to start backWardly down the grade.

The invention comprises the vehicle brake hereinafter described and claimed.

In the drawings, which represent one embodiment of the invention, Figure l is a plan view, showing a portion of the vehicle frame with the brake mechanism applied thereto; F ig. 2 is a side elevation, partly in section, and showing the brake shoes in normal inoperative position out of contact with the roadway; Fig. 3 is a cross section, on a larger scale, on the line 3-3, Fig. 2 looking in the direction of the arrows; and Fig. t is a detail view of a portion of the op- 4@ erating mechanism.

Referring to the drawings, the chassis or frame is indicated at 1 and comprises the usual longitudinal side members connected by cross ties or bars, two of which are indicated at 2 and 3 respectively.

4 indicates one ofthe axles, such as the rear axle, carrying the wheels 5.

The brake mechanism consists of one or a plurality, two being shown, of braking shoes 6, suitably arranged to be moved into contact with the roadway or pavement to produce the braking effect. These shoes may be 'of any suitable form and are shown as formed of rectangular cast or forged plates 5 5 with depending peripheral flanges 7 forming a cavity to receive the friction blocks 8 which are preferably made of some suitable hard, tough, wear-resisting material producing a high friction eiect with the roadway, blocks of carborundum being suitable for this purpose. The front end portion of each shoe is turned up to form a horn 9, as indicated in Fig. 2, so that when the shoe is applied to the ground it rides over knobs or bumps and will produce the friction eifect without turning over or digging into the roadway.

The brake shoes are movably connected to the vehicle frame or body and preferably are pivoted thereto. As shown, said shoes are pivotally connected at 6a to a suitable support l0, shown as formed of metal pipes and fittings therefor so connected as to form a rigid and substantial frame.' This frame 10 may be pivotally connected to the vehicle body, but is shown as pivotally connected at 11 to two split clamping members 12 detachably secured to the rear axle 4. Said frame is maintained in normal inoperative position with the brake shoes out of contact with the roadway or pavement by yielding tension springs 13, one thereof being connected to each side of the frame l0 above a brake shoe. The frame therefore is suspended from the rear axle and is inclined downwardly and rearwardly therefrom, so that when it is swung downwardly to move the brake shoes into contact with the roadway said frame forms a strut brace between the rear axle and the roadway and firmly sup ports the vehicle when the latter faces up a grade, the weight of the vehicle holding the brake shoes in contact with the roadway. If the vehicle is an automobile this arrange ment therefore enables the ordinary brakes to be slacked off, and the engine to be started without liability of the vehicle starting backwardly down the grade.

Some suitable means is provided for forcing the brake shoes 6 into contact with the roadway to produce the braking effect, either to prevent skidding on a slippery pavement or in case the ordinary brakes become inoperative or refuse to work. The mechanism shown comprises a suitable power driven Patented J an. 30, 19t?. l

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operating member, such as the disk 15 carried by the main powershaft 16 of the machine. This power shaft may be driven by a special motor, such as a gas engine or a motor operated by compressed air, steam, electricity, or the like, or may be a portion of the transmission mechanism between the engine and the vehicle wheels. In the form shown the shaft 16 is the constantly rotating main power shaft of the machine, and the disk 15 is splined to said shaft so that it constantly rotates therewith and may be moved longitudinally thereon. Said longitudinal movement is provided to enable said disk 15 to be moved into coperating relation with a winding member 17 on a drum shaft 18 shown as a vertical shaft journaled in bearings attached to the transverse frame member 3. The periphery of the disk 17 is preferably provided with some yielding or clinging friction producing material, such as leather, so as to prevent slip between 'the members 15 and 17 when in contact unless the torque exceeds a definite amount, so that when said members are engaged the disk 17 and drum shaft 18 are rotated frictionally by the engine power shaft 16. rlhe drum shaft 18 has connected thereto one end of a winding cord or cable 19, connected to the middle portion of a flexible operating member 20 having its opposite ends connected to the two sides of the frame member 10. Consequently whenever the drum shaft 18 is rotated the cable 19 is wound thereon and the frame 10 is oscillated about its pivots 11 to move the shoes 6 into contact with the ground.

The disk 15 may be operated either by a hand lever or by a foot pedal, such as by the pedal 21 pivoted on the foot board, and connected by a link 22 to a bell crank lever 23, the other arm of which is connected by a rod 2-1 to a lever 25. An elongated slot or several holes 25aM may be provided in the lever 25 for connecting the rod 24 at different points thereon to thereby vary the leverage exerted by the foot pedal. rlhe other end of said lever "25 is connected to the projecting end of one of the pins or trunnions 26 of an oscillating U-shaped frame 27, the side arms of which are provided with eccentric pins 28 having disk shaped cams 29 thereon. When the pedal 21 is pressed downwardly the U- shaped frame is oscillated to move the disks 28 against the peripheral portions of the disk 15 and move the same longitudinally on its shaft into contact with the disk 17. When the pedal is released the disk 15 and its operating mechanism are returned to normal position by a spiral compression spring 30 surrounding the operating shaft 16 and abutting said disk at one end and at its other end an adjustable sleeve 81 secured to said shaft.

Suitable means is preferably also provided for moving the brake slices into contact with the ground by hand in case the operating mechanism therefor refuses to work. The means shown comprise a hand lever 35 journaled on an axis 36 beneath the footboard, and having a depending arm 37 connected by a cord or cable 38 to the flexible operating member 20. 1f the operating mechanism refuses to work the hand lever can be operated to swing the frame 1() downwardly and press the shoes into contact with the roadway.

The construction described is very simple and can be readily applied to any vehicle or automobile. lt provides an effective brake for emergency use in case the ordinary brakes are inoperative or refuse to work.

It can also be used, to prevent skidding on otally connected to the axle and depending Y behind the same, and power driven friction mechanism for swinging said frame to press the shoe against the roadway.

3. A vehicle brake, comprising a frame pivotally connected to the axle, a brake shoe carried by said frame, a winding device, a flexible operating member connecting said device and frame, and means for rotating said winding device.

1l. A vehicle brake, comprising a frame pivotally connected to the vehicle, a brake shoe carried by said frame, a rotatable winding device, a fiexible operating member connecting said device andframe, and power operated mechanism for rotating said winding device.

5. A vehicle brake, comprising a frame pivotally connected to the rear axle, a brake shoe supported by said frame, yielding means for holding said frame with the brake shoe out of contact with the roadway, and power operated friction mechanism for swinging said frame to press the brake shoe against the roadway.

6. A vehicle brake, comprising a frame pivotally connected to the vehicle, a brake shoe supported thereby, a. rotatable winding device, a flexible operating member connecting said device and frame, a power operated driving member, and means for connecting said driving member and winding device to operate said brake. Y

7. A vehicle brake, comprising a supporting frame pivotally connected to the rear axle and depending behind the same, a brake shoe carried by saidf-rame, a rotatable winding device, a power operated shaft, a fric'- tion disk connected to said shaft and movable into coperative relation with said device, and a flexible operating member connecting said device and frame.

8. A vehicle brake, comprising a supporting frame pivotally connected to the lishing coperative relation between said rear aXle and depending behind the same, a disk and winding device. 10 brake shoe carried by said frame, a rotatable In testimony whereof, I have hereunto set winding device, a power operated shaft, a my hand.

.5 friction disk connected to said shaft and ISAAC E. MCCRACKEN.

movable into cooperative relation with said Witnesses: device, a flexible operating member connect- GLENN H. LERESGHE, ing said device and frame, and means estab- WILLIAM B. WHARTON.

Gopies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents.

' Washington,D C. 

